I'd like to write a Thin handler that takes in a request, does some
logic, and optionally forwards the request to Rails.  Is this
possible ?  If it is, is possible for the handler to re-acquire the
response after the request has been filled?

An example use case: a request with HTTP Basic Authentication comes
in.  The Thin handler catches it and talks to the database to verify
the credentials.  If the requesting user isn't authorized, the Thin
handler returns an 'Unauthorized' response and exits.  If the
requesting user is authorized, the request is forwarded to Rails to be
fulfilled.

Glad to see you're interested in Thin!

That's very easy w/ Rack. You can build a wrapper around the Rails
adapter. Those wrappers are called Middlewares in Rack and Handlers
are called Adapter.

Here's a very simple example:

class MyAwesomeMiddleware
  def initialize(rails_app)
    @rails_app = rails_app
  end

  def call(env)
    # Select the app to send the request to ...
    app = if forward_to_rails?(env)
      @rails_app
    else
      @some_other_app
    end

    status, headers, body = app.call(env)

    # You can alter the status
    # the response headers and the body.
    body += 'crazy delicious footer!'
    headers['HTTP_X_AWESOME'] = 'fo sho yo'

    status, headers, body
  end

  def forward_to_rails?(env)
    # You have access to all request headers like PATH_INFO through
then env Hash.
  end
end

== In your Rack config file: config.ru
use MyAwesomeMiddleware, YourOtherApp.new
run Rack::Adapter::Rails.new(:root => '/path/to/your/
rails_app', :environment => 'production')
==

then start thin w/: thin start -r config.ru

Rack also comes with a couple authenticators, maybe that could be
useful to you:

protected_app = Rack::Auth::Basic.new(rails_app) do |username,
password|
  'secret' == password
end
protected_app.realm = 'Awesome 2.0'

run protected_app

You can get more info in Rack doc http://rack.rubyforge.org/doc/
Or let me know if you need help w/ that.

On Feb 20, 5:17 pm, Alex Payne <a...@al3x.net> wrote: